ORGANIC-COMPOUNDS OF RADIONUCLIDES IN SOIL SOLUTIONS AND THEIR ROLE IN THE UPTAKE OF ELEMENTS INTO PLANTS

In model experiments with the introduction of a radioactive label (35C, Ca-45, Fe-59, Sr-85, I-125) into five types of zonal soils, it was established by radio-gel chromatography that in soil solutions Fe-59 and I-125 are completely incorporated and S-35, Ca-45, and Sr-85 are 60-90% incorporated into from one to three fractions of organic compounds with molecular weights 4.10(2)-6.10(4). It was shown that significant variations between soils in the accessibility for plants of such radionuclides as Ca-45, Fe-59, Sr-85, and I-125 are associated with the different degree of their passage into the soil solution, as well as with differences in their distribution among molecular-weight-fractions of water-soluble organic compounds.